Subaru’s Contradictory Oil Recommendation.....

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We have a 2019 Outback with the 2.5L (non-turbo/non-DI) engine. The warranty OCI is 6k miles. In reading the owner's manual (mostly to figure out the technology) I came across the following pages in re: oil.

First, on page 11-13, read the "Note" at the lower left side.

I am NOT posting this to re-ignite the "thin versus thick" bonfire.

However, I interpret that statement to ask, "do you want fuel economy or protection?"

Now look at the right column under "Synthetic Oil," and read the first sentence.

On page 12-4, read the second bullet point under the second note. It re-affirms the statement on page 11-13.

On page 12-5, Subaru is pushing the use of 0w-20. However, they claim conventional oil can be used in viscosities of 5w-30 or 5w-40.

That 2.5L supposedly has a long timing chain. My friend with a 2015 Legacy 2.5L was told by the service manager that synthetic oil was required in order to protect the timing chain.

Oddly enough, the 2019 3.6L engine specs 5w-30 conventional oil.

I plan to use Platinum Ultra 5w-30 after the factory fill is changed.





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DOH!

Why does that second pic keep showing upside down?
 
Good luck finding a conventional 5w-40.

However, 0w-40 and 5w-40 does work pretty nice in the FB25 engines. They don't have one long chain, but two normal chains with separate tensioners and guides.
 
I think the jist of it is, use 0W20 for each OCI, top up with whatever SN oil you've got if no 0W20 is available , then use 0W20 again. I haven't had to top up yet over an OCI but I'll probably use some 5W30 just to keep the viscosity up later in the OCI.
What oil temp does yours run at just cruising on the highway? Ours is up around 200F often in moderate temps, and then if it revs a bit climbing a long hill, it can go a bit higher. Once I'm out of warranty I'll use syn 5W30.
 
I don't know about the current gen Forester / Outback,

But the previous gen had an oil temp display available on the customizable info display.
 
Originally Posted by Miller88
I don't know about the current gen Forester / Outback,

But the previous gen had an oil temp display available on the customizable info display.

Yep, I like to show oil temp and throttle position so I can eek out some more mpg. On the base radio its under 'car info'and you can pick what you want to see there.
 
Originally Posted by Miller88
I do wish there were more available options. I'd like coolant temperature too.

I have oil temp, throttle position and trip time.

What's your oil temp run at normally? If I ran the manuals cruising rpm it would be maybe at 210F?. It seems very rpm dependent.
I haven't tried my Ultra Gauge on the Outback yet, as I don't drive it that much, and I found it caused to blank out the Focus's dash once in a while(all warning lights on, no ODO,speedo, or rpm), so I don't use it unless I have a specific issue I'm looking for.
 
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Thanks.

Less reading on the owner's manual oil pages and back to re-reading the tech pages.
 
I think my manual has the same wording for the 2.5l and it is head-scratching.
Why does conventional oil need to be used for top off??
I guess the note tells you to have the dealer change the oil and filter, anyway, so you shouldn't even need to know about what oil to use. They should tell you to have the dealer top it off, too!
 
if an oil change is REQUIRED by the STEALER its FREE, but recommended is just trying to push-scare into their overpriced services + generally simple things like oil changes are done buy the rookies-learners in the shop. no harm meant as everybody has to learn + HOPEFULLY do it right
 
Originally Posted by Virtus_Probi
I think my manual has the same wording for the 2.5l and it is head-scratching.
Why does conventional oil need to be used for top off??
................


Why synthetic in the 2.5L but conventional in the 3.6L? Engine tolerances?

What really raises an eyebrow with me is their statement...... "However, in hot weather oil of higher viscosity is required to properly lubricate the engine."

And they say it twice, on pages 11-13 and 12-4.

What? 0w-20 does not properly lubricate the engine when it's hot? That's why I will use Ultra 5w-30 April to October, then 0w-20 during the "non-hot weather months."
 
The 3.6 is an older design and uses heavy chains where the EJ used a belt. The FA/FB uses chains as well, but is designed to run 0W20 for fuel economy. You'd be foolish to try to run a 20wt oil in an EJ, but I doubt you'd have any issues running a 0W20 year round like the hundreds of thousands of other Subaru owners who only have their oil changed at the dealer. However, you can run a thin 30wt like Pennzoil Platinum and not see any real hit to fuel economy either, and with a good oil like that you're highly unlikely to ever have an engine issue that was caused by either a 20wt or 30wt oil. Here's a pic of the 3.6 timing chains- these engines are big and heavy, and really a late 1980's design as it was heavily based off the EJ series.


Subie.JPG
 
I personally like Subaru's engineers and their subtle "hints" used over the years. They say what many of us already know... if you plan to run it hard and drive spirited, use anything other than the watered down 0W20. If you're grampa trying to eek out every MPG and follow CAFE regulation, use the 0W20...

I personally use nothing thinner than a 5W30 in my Legacy with the Turbocharged EJ255 and its at 162000 miles right now and runs flawlessly.
 
Originally Posted by racin4ds
I personally like Subaru's engineers and their subtle "hints" used over the years. They say what many of us already know... if you plan to run it hard and drive spirited, use anything other than the watered down 0W20. If you're grampa trying to eek out every MPG and follow CAFE regulation, use the 0W20....


Pretty much exactly what i was thinking


When the WRX crown almost universally "accepted" Rotella T6 5W-40 as their "go-to" oil, I'm sure Subi engineers nodded theirs heads in collective approval
 
Originally Posted by racin4ds
I personally use nothing thinner than a 5W30 in my Legacy with the Turbocharged EJ255 and its at 162000 miles right now and runs flawlessly.


Umm, that's because your Legacy has an EJ255 engine and requires 5W30...
 
Folks like to point out when the manual says "adequate protection" when linked to 0/5w20. Well, in this manual it actually says "for optimum performance and protection..."

I'm not commenting on the oil per say, more so the posters every time this stuff comes up. I'm sure the Subbie will run fine on any viscosity printed in the Owner's Manual... syn or dino.



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